SECOND SKRIKS; ITLMONATA 



MANUAL 



CONGHOLOGV; 



STRUCTURAL AND SYSTEMATIC. 



WITH [ILLUSTRATIONS OF TII'K SPRCIKS. 



I OTN l> KD I',V 



GEORGE W. TRYON, JR. 



INTKI) 



HENRY A. PILSBRY, Sc.l)., 



!IK AcAMKMV OF 



XATCRAI 



Part 



PHILADELPHIA : 



Published by the Conchological Section 



\I>F,MY OF NATURAL SCIENi 



OF PHILADELPHIA 



